1. Field of the Invention
The use of cam cleats for sail boats is well known in the prior art.
The rope is either pressed between two conveniently-shaped toothed cams or between a cam and a guide. With a correctly-chosen initial bite angle between cam and rope, any pull on the rope will draw the cam. The rope will be more and more pressed as the load increases.
The release is obtained by upward-pulling the rope parallely to the teeth.
When the rope guide is a sheave, the sheave groove prevents the rope from being pulled parallely to the teeth, and this is a strong limitation to the use of cam cleats with the sheaves, because the only release possibility consists in pulling back the rope by hand or by means of a winch in order to suppress any load on the cam before manually opening it.
Conventional cam cleats become harder to release as the wind increases and have earned the reputation for not releasing at the critical moment.
Tests have shown that an upward force of 40 to 60 kgs is needed to release a rope engaged in a cam cleat with a load of 130 kgs: well beyond the force that a man can easily develop at the end of his arm.
2. Description of the Prior Art
To our knowledge, nowhere in the device of the prior art is there to be found a direct solution to the easy release of a camming cleat for sailboat equipment in gusty conditions.
However, the U.S. Pat. No. 3,580,209 is a different approach of this problem, as the cam is replaced by a pivotally-mounted cam arm with a friction-controlled toothed wheel rotatably mounted at its end.
Above a predetermined force, the sheet will controllably play out.
This is not a general solution to the problem, for, in most applications, it is necessary to let the sheet, or the halyard, run totally free after releasing, notwithstanding the difficulty of setting the point at which the rope must begin to play out.